Withaferin A, a candidate drug for lupus nephritis, confers renal protection via Pon1‑mediated attenuation of oxidative stress.

Lupus nephritis (LN) is a severe manifestation of systemic lupus erythematosus (SLE). It is characterized by autoantibody deposition and immune complex formation within the kidney, leading to progressive nephron loss and end‑stage renal disease. Suppression of immunology is a cornerstone for managing LN. The present study identified withaferin A (WA) as a promising therapeutic candidate for SLE via connectivity map analysis and validated its efficacy in ameliorating LN in an MRL/lpr mouse model. Candidate drugs for LN were identified via the Connectivity Map database by integrating transcriptomic signatures from GSE135779, GSE162577 and GSE142016. An animal model was established to evaluate the therapeutic efficacy of WA on LN‑associated inflammation and splenic dysfunction, followed by RNA‑sequencing analysis. To elucidate the mechanistic role of PON1 in WA‑mediated protection, siRNA‑mediated knockdown and plasmid‑driven overexpression were performed in HK‑2 cells. Furthermore, the direct impact of WA was assessed using isolated primary B cells. WA improved renal function by mitigating splenic immune cell dysregulation and attenuating renal inflammation. Mechanistically, RNA‑sequencing analysis and functional validation revealed that WA upregulated paraoxonase 1 (Pon1) expression, which in turn alleviates renal injury by decreasing reactive oxygen species via the peroxisome proliferator‑activated receptor signaling pathway. Pon1 activation enhanced cell viability, suppressed inflammatory responses and decreased oxidative stress in HK‑2 cells, underscoring its potential as a novel therapeutic target for LN. Collectively, the findings demonstrate WA is a viable candidate for SLE/LN treatment and Pon1 is a pivotal mediator of its protective effects, thereby providing a dual‑strategy insight for clinical intervention.